Solve simultaneous equation....4x-5y and 2x+y=4 4x - 5y = 20and2x + y = 4 how to solve simultaneous equation?

Question

asked Oct 7, 2023 201k views

1 Answer

Thunderstriker · Answer 1 · 2023-10-13T01:51:18+0000

Answer:

(
(20)/(7) , -
(12)/(7) )

Explanation:

4x - 5y = 20 → (1)

2x + y = 4 → (2)

subtract 2x fro both sides in (2)

y = 4 - 2x → (3)

substitute y = 4 - 2x into (1)

4x - 5(4 - 2x) = 20 ( distribute parenthesis and simplify left side )

4x - 20 + 10x = 20

14x - 20 = 20 ( add 20 to both sides )

14x = 40 ( divide both sides by 14 )

x =
(40)/(14) =
(20)/(7)

substitute this value into (3)

y = 4 - 2(
(20)/(7) ) =
(28)/(7) -
(40)/(7) = -
(12)/(7)

solution is (
(20)/(7) , -
(12)/(7) )